Automobile transmissions are well known in the art. For example, some known systems include three-piece assemblies having two pistons and an uncontained spring that must be preloaded during assembly. U.S. Pat. No. 5,893,445 (Dover) is incorporated herein by reference, and provides another example of a piston assembly for engaging the clutch of a transmission. The design in Dover includes a single piston with an overmolded seal for enabling pressurized actuation of a piston in order to engage a clutch and/or clutch pack and a split release spring retained in a slot for urging the piston away from the clutch pack. In these conventional systems, the multiple components require increased inventory management and results in an increased chance of misassembly. Overmolded seals and dual pistons can be costly to produce. Furthermore, these systems typically use the seal as a positive stop for the piston, which can lead to inefficiencies in engagement of the clutch due to the compressibility and less accurate tolerances of rubber seals.